A drag-reducing agent (DRA) is one that substantially reduces the friction loss that results from the turbulent flow of a fluid, and thereby increases the flow capability of pipelines, hoses and other conduits in which liquids flow. Certain polymers are known to function as DRAs, particularly in hydrocarbon liquids. Such polymers may be dissolved in hydrocarbon liquids in order, for example, to increase liquid flow, to provide for the use of a smaller diameter pipe for a given flow capacity, or to reduce the cost of pumping hydrocarbon liquids.
A method of improving the combustion efficiency of a fuel-burning device is to add an appropriate polymer to the fuel of the fuel-burning device and to burn the fuel with the polymer in the fuel-burning device. In general, the improvement in combustion efficiency of a four-cycle diesel engine operating on traditional polymeric-additive-treated diesel fuel vs. neat diesel fuel is superior to the improvement in combustion efficiency of a four-cycle gasoline engine operating on traditional polymeric-additive-treated gasoline vs. neat gasoline. Whereas the superior improvement in combustion efficiency of a diesel engine operating on traditional polymeric-additive-treated diesel fuel depends in part upon the molecular weight of the polymer, the efficiency of a polymer fuel additive, as well as the efficiency of a polymer DRA, depends more specifically upon the polymer's viscoelastic properties.